I have been working on making some of these and here is the problem. The left side of the insert has a ridge that has to be routed. And the far-side of the insert has two tabs that have to hook into the table itself. Both of these, however, are just the start. The other problem is the frame for anti-kickback, this creates an issue for just raising the blade to cut through the insert. Now, the insert that comes with the saw is not made of wood, so it is fairly stable, even though it is almost cut all the way through the length. Has anyone thought of a clever way to customize these for this saw (or one like it)? And, for those who have purchased the Bosch blanks, what are they made of? And do these take these problem areas into consideration? Thanks, as always.

I have made several zero clearance inserts for my Bosch saw. My approach could certainly be improved upon, but I have been using my inserts for several years with zero problems. You do have to route or chisel a channel for the ridge in the table on the left side of the blade, but the other issues you mentioned can be by-passed. If your new insert is carefully machined there is no need for tongues on the back side like the factory insert; I have never had the friction fit of the insert fail. I just ditched the cumbersome factory anti-kickback pawls and attached a splitter to each insert. I don’t feel like I’m being careless in doing so – just practical; the splitter keeps the kerf open thereby eliminating a major cause of kickback. As a bonus, you don’t have to sand out the grooves in your lumber left by the pawls.

I rabbeted the perimeter, and took the riving knife OFF as I was raising the blade – I then used a JIGSAW to notch out the opening for the riving knife behing the blade slot, and put the riving knife back on. worked like a charm.

I’ve seen where someone built one complicated one, then routed a shallow dado on the top for replacable masonite strips. Much easier than building several complicated inserts. I wish I had a picture to show you. Sorry.

I use a Bosch blank on my Bosch 4000. They are plastic with metal slotted tail for anti-kick paws and riving bracket, 4 set screws for height adjustment, then four pan head countersunk screws for locking down tight. The insert is OK, wish it was made of something more sturdy than plastic, but functions well. If you make your own, you will see four threaded holes for the lock down screws. Therefore, no tabs required with hold down screws and are handy for raising blade up through blank.

I tried to first basic approach and then discovered the higher ledge on the left side of the table throat. That was after I’d found out about the wrongs of using 1/2” birch ply but had completed a nice shape template. I dropped back to 1/2” MDF, pulled out the router table and went to work. I was able to create several blanks from the template (I used 1” brads to attach the template to the MDF). Yes, the Anti-kickback pawl doesn’t pass through the insert, but then, I need to use zero clearance inserts for dado or rabbit work where they interfere with the pass of the wood across the dado. I use the pawl for ripping longer pieces. Also, I depend upon a close fit and friction to keep the insert in place. It’s working.

I bought an insert from P’tree for my G0444Z. Found it to be a little undersized, so I added 6 set screws around the perimeter so I could thighten up the fit. Hope yours fit better. Mine works fine now, just a bit of a hassle to modify.Bill